It doesn’t truly matter whether it was a sucker punch or simply a punch.

In professional football, the franchise quarterback is held to a higher standard — and higher paycheck. Broadway Joe Namath was a jet-setter/night owl/ladies man whose favorite target would have been Johnnie Walker had he been a teammate.

But his teammates respected him because he walked the talk as their leader and the Fu-Manchu’d face of the franchise. He always had their backs.

Ryan Fitzpatrick is now the Jets quarterback, starting with Thursday night’s preseason opener against the Lions, because Geno Smith should have walked away from the kindergarten confrontation that left him with a broken jaw and a broken Jets career. Whether he owed IK Enemkpali $600 or $6,000 or 60 cents.

There are very few Boy Scouts inside NFL locker rooms, and a disturbing lack of maturity, caution and common sense outside of them. Raging testosterone levels are the rule rather than the exception in the boys-will-be-boys culture of all sports.

But as an NFL owner, as an organization, as a coach, as a teammate and as a fan, you want your quarterback to exhibit calm and poise in the face of chaos and turbulence, on the field and off. You want him to be a model of decorum and professionalism. You want him to be your battlefield commander around whom the rest of the team rallies. The head coach wants his quarterback to be an extension of him, a trusted lieutenant.

Ideally, you want him to be Peyton Manning. Or Eli Manning. Or Aaron Rodgers. Or Andrew Luck. Or, yes, Tom Brady. There is too much at stake for everyone, too much invested, financially and emotionally, for the quarterback to put himself in an uncompromising position — or in harm’s way.

I think this is the last straw for Geno Smith.

Jets coach Todd BowlesBill Kostroun

Todd Bowles can talk about changing the culture all he wants, but good luck to him if a bad apple like Enemkpali hasn’t learned, if from no other source than Roger Goodell’s Personal Conduct Policy, that the laws of the wild are not tolerated, even in a league of pros and cons. Rex Ryan, who scooped up Enemkpali on Wednesday, may have run a loose Jets ship, but let’s not forget that Enemkpali never sucker-punched Smith under Ryan’s watch.

“I think it’s more important for my teammates to see how I react to it, more than anything,” Smith said afterward.

What are his teammates to think now?

How, exactly, will they be able to trust him again? How will Bowles be able to trust him again? How will general manager Mike Maccagnan be able to trust him again? How will Woody Johnson be able to trust him again?

It escalated inexcusably into a symbolic black eye for the tortured franchise so eager for a fresh start with bright new leadership.

Because it only calls into question Smith’s judgment. There has been a long list of misfits who proved ill-equipped to be a franchise quarterback — but somehow, Ryan Leaf was never socked by a teammate in his locker room. Robert Griffin III probably wouldn’t have won the popular vote in the Washington locker room last season, but he was never KO’d by anyone.

Make no mistake, Smith is the victim here. But if it is true that he stuck a finger in Enemkpali’s face, or dared him to act — as ESPN’s Ryan Clark, a former Steeler, said Wednesday — then he is hardly blameless for being victimized. When you are the designated driver of the Porsche, you steer clear of trouble at all costs. This was a head-on collision that could have and should have been avoided. And if some of his teammates don’t know it, Bowles sure does.

Bowles arrived at Florham Park as a classy, no-nonsense professional who has been preaching accountability from Day 1. He didn’t sign up to be head coach of Romper Room.

The signing of Brandon Marshall and expected emergence of Jace Amaro afforded Smith the chance to make instead of break. With the prospect of an elite defense, even without the suspended Sheldon Richardson, Smith’s mandate was to cut down on the foolish mistakes that have marked his career.

This may have been the worst one of all. Jets career intercepted. Jets career fumbled away.